Difference btwn EPA type woodstoves - with cats and without??

[kayakkeith]

I have a Woodstock Keystone with a catalytic unit in it. I have some friends that have the Jotul stoves that they say are EPA approved but I dont think they have the cat - what is the difference if they dont have a cat - how do they burn the extra stuff,etc

 

[cmonSTART]

http://www.woodheat.org/technology/woodstoves.htm

Under the subheading of "Combustion Design" is a good description.

 

[Hardrockmaple]

Here ya go.

https://www.hearth.com/econtent/index.php/articles/choosing_and_using_wstove

 

[Renovation]

Here ya go.

https://www.hearth.com/econtent/index.php/articles/choosing_and_using_wstove

Excellent resource.

One thing that I'd suggest updating is the predicted cat life. That article is from 1992, and estimates cat replacement at 2 - 3 years. My understanding is modern cat stoves have a cat life more like 5 - 6 years. For example, Blaze King has a sliding cat warranty that ends at about 6 years.

Agreed?

If so, I'll send Craig a note asking him to update the article.

 

[Hardrockmaple]

Here ya go.

https://www.hearth.com/econtent/index.php/articles/choosing_and_using_wstove

Excellent resource.

One thing that I'd suggest updating is the predicted cat life. That article is from 1992, and estimates cat replacement at 2 - 3 years. My understanding is modern cat stoves have a cat life more like 5 - 6 years. For example, Blaze King has a sliding cat warranty that ends at about 6 years.

Agreed?

If so, I'll send Craig a note asking him to update the article.

Dunno....Condar recommends 12,000 hrs., so if you burn 24/7 for 3-4 months a year..... I swap mine out every 3 years for example.

see chart below.

http://www.woodstovecombustors.com/replacement.html

rgds.

 

[North of 60]

24/7 for 8 to 9 month's a year. Yr 5 no smoke and chimney clean. Must be the evil pine and spruce I feed it. If it aint broke dont fix it. I will pull my cat for the 1st time this summer and go with a new gasket as pulling stove anyways to renovate.

 

[Hardrockmaple]

Hey, my 72 year old neighbor has a 10 year old BK King. Burns only maple, birch and apple. He still hasn't replaced his cat.

<shrug>.... to each their own.

 

[North of 60]

Hey, my 72 year old neighbor has a 10 year old BK King. Burns only maple, birch and apple. He still hasn't replaced his cat.

<shrug>.... to each their own.

Does his stove smoke?

 

[Hardrockmaple]

No.

 

[Renovation]

One thing that I'd suggest updating is the predicted cat life. That article is from 1992, and estimates cat replacement at 2 - 3 years. My understanding is modern cat stoves have a cat life more like 5 - 6 years. For example, Blaze King has a sliding cat warranty that ends at about 6 years.

Agreed?

Dunno....Condar recommends 12,000 hrs., so if you burn 24/7 for 3-4 months a year..... I swap mine out every 3 years for example.

see chart below.

http://www.woodstovecombustors.com/replacement.html

rgds.

Thanks, HRM, that really is an interesting link.

A couple of things jumped out at me.

First, it's 12,000 hour recommendation is based on the cat losing 25% effectiveness. I'm not sure how many people would be that conscientious--and I mean that as a real question, not for rhetoric.

Second, I was hoping that chart would show how much that 25% loss translates into loss of overall burning efficiency? In other words, what percent more wood would (a woodchuck chuck, no!) a wood stove burn with that loss of cat efficiency? Any ideas?

Back to you, how do you determine when to swap out your cat? Do you do it by date, or some stove symptom?

Enquiring minds want to know!

Have a great night.

 

[begreen]

Hey, my 72 year old neighbor has a 10 year old BK King. Burns only maple, birch and apple. He still hasn't replaced his cat.

<shrug>.... to each their own.

Does his stove smoke?

At ten years old, it's still too young to smoke.

 

[Backwoods Savage]

Many folks do get 10 years or more from their cats. What some folks do not realize is a lot of that depends upon the wood you are burning. Burn poor fuel? Expect poor results from both the fire and the cat.

 

[Hardrockmaple]

Many folks do get 10 years or more from their cats. What some folks do not realize is a lot of that depends upon the wood you are burning. Burn poor fuel? Expect poor results from both the fire and the cat.

Another important variable IMO is how you burn. I keep my stove on 500* as much as I can, my neighbor with the BK King OTOH burns damper closed/air wide open all the time. I burn 3 cords, he burns 6 or more.

 

[raybonz]

Here ya go.

https://www.hearth.com/econtent/index.php/articles/choosing_and_using_wstove

Excellent resource.

One thing that I'd suggest updating is the predicted cat life. That article is from 1992, and estimates cat replacement at 2 - 3 years. My understanding is modern cat stoves have a cat life more like 5 - 6 years. For example, Blaze King has a sliding cat warranty that ends at about 6 years.

Agreed?

If so, I'll send Craig a note asking him to update the article.

My stove was new in 1988 and the cat literature from Owens Corning said to expect 6 yrs. back then and I have gotten 6 yrs. + right along.. Pretty sure the cats haven't changed since they were introduced ..

Ray